Starting and Ignition Systems
Gas turbines unlike piston engines employ a continuous combustion process to provide the heat input to their working cycle. Once ignited the fuel burns continuously until the engine is shut down, at this point the combustion is extinguished by cutting off the fuel supply. When a gas turbine is started, a means of igniting the fuel is required, in most cases this is provided by an electric spark.
One or more ignitor plugs are placed in the combustion chamber usually close to a fuel burner nozzle. When the fuel is switched on the spray from the burner reaches the plug and ignites. Most small gas turbines only have one ignitor plug, but in some cases when an engine is constructed with an annular combustion chamber, two are fitted at opposite sides of the combustion chamber.

Ingination
Like piston engines GTEs are also fitted with dual ignition systems. These are rated in Joules (watt per second or w/s). The life of the igniters is extended by limiting the amount of energy required. So if continuous use is necessary, for example in heavy rain, snow and or turbulence, power output is reduced. Most systems have low and high output igniters and both are used during start where the low output igniter is used for continuous use. Modern electronic igniter systems can be regulated in energy output (J) as required

High Tension Ignition
This process is not dissimilar to piston engine ignition systems. A step up transformer or "ignition coil" provides a high voltage spark. A DC current is applied to the transformer primary and is interrupted by contacts in a trembler mechanism. The trembler mechanism is operated by the magnetic field from the transformer windings. This arrangement is similar to an ordinary electric bell and vibrates many times per second, this produces a stream of sparks at an igniter plug which is connected to the